Lake Erie is one of the most popular fisheries in our state as it accounted, in 2021, for 14% of the total Great Lakes angling effort, 31% of the catch, a catch rate three times the other Great Lakes waters combined, and an angling intensity more than 54% that of the other Great Lakes waters in our state.
Fisheries surveys and other companion surveys are critical to maintaining this fishery, which Michigan shares with New York, Ohio and Pennsylvania and the Canadian Province of Ontario.
The DNR does two surveys using the R/V Channel Cat to obtain information from Lake Erie’s complex fisheries community:
- The first is a bottom trawl survey that examines the number of young-of-year walleye and yellow perch in Michigan waters of Lake Erie, contributing to interagency knowledge about reproduction for these two species. This survey, in its ninth year, also documents the relative abundance of forage fish species that live near the bottom.
- The second survey is a gillnet survey that samples the abundance and age structure of yearling and older walleye in Michigan waters. These data drive the population models that are used to determine the total allowable catch and daily bag limits for walleye in this valuable water. This survey was conducted in October at four locations with two index stations (Stony Point and Luna Pier) that have been sampled every year for 45 years.
Walleye populations remain near the all-time high, with trawling indicating that recruitment continues to be very strong. The age-0 walleye catch rate in the bottom trawl (14 fish caught per 10-minute trawl tow) was comparable to the past two years, coming in above the nine-year average of 11 fish per 10-minute trawl tow. Walleye reproduction during the past seven years has been strong, with multiple large year classes beginning in 2015.
Similarly, older walleye were caught in gillnets this year at rates (150 fish per net lift) 40% greater than the long-term average. This was a 150% increase from last year and the highest rate at index stations since 2005. Of the 404 walleye captured and measured for biological data, nearly 75% were above the minimum size of 15 inches. All these fish have had their stomach contents examined; 80% had food present, with 66% of them having eaten gizzard shad. More information on these larger adults will be gathered this winter when the fish are aged.
Yellow perch populations were found to be holding their own. While reproduction was down, as the trawl catch rate of age-0 yellow perch dropped from last year (>1,200 fish per 10-minute trawl tow to 157 fish per 10-minute trawl tow). This level of young-of-year relative abundance is not unprecedented; in fact, it is comparable to observations during the first four years of the survey (2014-2017).
Survival of young-of-year yellow perch to older ages is needed to increase the abundance of harvestable-sized fish. This seems to be occurring, as the catch rate of yearling and older yellow perch (46 fish per 10-minute trawl tow) was at a six-year high and above the time series average of 33 fish per10 minute trawl tow. Creel data from clerks’ conversations with anglers will be available later this fall and should show whether these fish are appearing in the recreational fishery.
Sufficient numbers of forage fish are required to support Lake Erie’s important recreational fisheries. Even though bottom trawling shows that forage catch rates were down, driven by a decrease in age-0 white perch and age-0 yellow perch, anglers shouldn’t be concerned about their favorite target species running out of food.
“These collections are on the low end of the range of forage catch rates observed during the last nine years. However, this doesn’t mean that there is a lack of forage in the lake, as our trawls only sample fish that live near the bottom,” said Todd Wills, Lake St. Clair Fisheries Research Station manager. “Walleye health, as measured by visceral (stomach) fat, is very good, and their diets often contain gizzard shad, which are not sampled well by our trawls and live higher in the water column.”
The DNR will know much more about this remarkable urban fishery when all of the fish are aged, survey data is fully examined, creel census data is proofed and creel census biological data is available in early 2023.